JavaScript学生信息系统

const readline = require("readline-sync"); //输出功能
//登录注册数组
let user = [{
        account: "d",
        password: 1
    },
    {
        account: "e",
        password: 2
    },
    {
        account: "f",
        password: 3
    }
]
//学生信息数组
let user1 = [{
        id: 1,
        name: 'liu',
        age: '18',
        gender: 'male',
        score: '98'
    },
    {
        id: 2,
        name: 'chen',
        age: '20',
        gender: 'famale',
        score: '100'
    },
    {
        id: 3,
        name: 'zhang',
        age: '17',
        gender: 'male',
        score: '77'
    },
    {
        id: 4,
        name: 'li',
        age: '22',
        gender: 'famale',
        score: '65'
    },
    {
        id: 5,
        name: 'sun',
        age: '19',
        gender: 'male',
        score: '80'
    }
];
// //注册
function regsiter(user) {
    let status = true;
    while (status) {
        let x = 1;
        console.log("请输入注册账号：");
        let account = readline.question();
        for (let index = 0; index < user.length; index++) {
            if (account == user[index].account) {
                console.log("账号已存在");
                x++;
            }
        }
        if (x == 1) {
            console.log("请输入注册密码：");
            let password = readline.question();
            user.push({
                account,
                password
            });
            console.log("注册成功！跳转登录页面...");
            return;
        }
    }
}
//登录
function login(user) {
    let status = true; //状态值
    while (status) {
        let x = 1; //状态值
        console.log("请输入账号：");
        let account = readline.question();
        console.log("请输入密码：");
        let password = readline.question();
        for (let index = 0; index < user.length; index++) {
            if (account == user[index].account && password == user[index].password) {
                console.log("登录成功");
                x++;
                return;
            }
        }
        if (x == 1) {
            console.log("登录失败");
        }
    }
}
// //选择业务
function option() {
    console.log("请选择业务：1.登录 2.注册 3.退出");
    let choice = readline.question() - 0;
    while (isNaN(choice) || choice < 1 || choice > 3) {
        console.log("输入有误，请重输：");
        choice = readline.question() - 0;
    }
    switch (choice) {
        case 3:
            console.log("谢谢使用，再见");
            break;
        case 2:
            regsiter(user);
            login(user);
            break;
        case 1:
            login(user);
            break;

        default:
            break;
    }


}
option();
// //查询
function search(user1) {
    console.log("请选择查询方式：1.查询所有 2.分类查询");
    let choice = readline.question() - 0; //查询方式
    while (isNaN(choice) || choice < 1 || choice > 2) {
        console.log("选择有误，请重输：");
        choice = readline.question() - 0;
    }
    switch (choice) {
        case 2: //分类查询
            console.log("请选择查询类型：1.姓名 2.年龄 3.性别 4.成绩");
            let choice1 = readline.question() - 0; //查询类型
            while (isNaN(choice1) || choice1 < 1 || choice1 > 4) {
                console.log("请重输");
                choice1 = readline.question() - 0;
            }
            console.log("请输入查询信息");
            let message = readline.question();
            for (let i = 0; i < user1.length; i++) {
                let a = ["id", "name", "age", "gender", "score"]; //用数组拿到对象的键名
                let b = a[choice1]; //根据用户输入找到对应的键，用数组拿出来
                let str = user1[i][b]; //在对象中，要查询的是键对应的值，用字符串把值取出来
                if (str.includes(message)) {
                    console.log(user1[i]); //如果字符串包含所要找的字符，那么输出这个对象
                }
            }
            break;
        case 1: //查询所有
            for (let index = 0; index < user1.length; index++) {
                console.log(user1[index]);
            }
            break;
        default:
            break;
    }
}
// //新增
function add(user1, length) {
    let status = true; //状态值
    console.log("请输入新增学生姓名：");
    let name = readline.question();
    let reg1 = /[a-zA-Z]/; //使用正则表达式来确保学生姓名输入正确
    while (!reg1.test(name)) {
        console.log("学生姓名不得包含数字和非法字符，请重输");
        name = readline.question();
    }
    console.log("请输入新增学生年龄：");
    let age = readline.question() - 0;
    while (isNaN(age) || age < 1) { //保证输出正确年龄
        console.log("请重输");
        age = readline.question() - 0;
    }
    console.log("请输入新增学生性别：");
    let gender = readline.question();
    console.log("请输入新增学生成绩：");
    let score = readline.question() - 0;
    while (isNaN(score) || score < 0 || score > 100) { //保证输出正确成绩
        console.log("请重输");
        score = readline.question() - 0;
    }
    console.log("新增成功! 该学生信息如下：");
    length++;
    user1.push({
        id: length,
        name,
        age,
        gender,
        score
    })
    console.log(user1[length - 1]);
}
// //修改
function alter(user1, length) {
    console.log("请输入要修改的学生学号：");
    let number = readline.question(); //学生学号
    while (isNaN(number) || number < 1 || number > length) {
        console.log("输入有误:请重输");
        number = readline.question();
    }
    console.log("当前学生信息如下：");
    console.log(user1[number - 1]);
    console.log("请选择要修改的信息： 1.姓名 2.年龄 3.性别 4.成绩");
    let choice1 = ["姓名", "年龄", "性别", "成绩"]; //信息对应汉字
    let choice3 = ["name", "age", "gender", "score"]; //信息对应对象里面的键名
    let choice = readline.question() - 0; //用户输入修改的信息对应编号1,2,3,4
    while (isNaN(choice) || choice < 1 || choice > 4) {
        console.log("请重输：");
        choice = readline.question() - 0; //如果用户输入的不是数字或者输入了错误的数字，加以提示
    }
    console.log(`您要修改的是${choice1[choice - 1]}`);
    console.log("确认请按1，取消请按2"); //确认要修改信息
    let choice2 = readline.question() - 0;
    if (choice2 == 1) {
        console.log("请输入新的数据");
        let data = readline.question(); //输入新信息
        console.log("修改成功！ 该学生信息如下：");
        user1[number - 1][`${choice3[choice - 1]}`] = data; //修改对象里面的值，方法类似数组
        console.log(user1[number - 1]); //修改后的信息
        return;
    } else {
        return; //如果不修改，就退出
    }

}
//删除
function del(user1, length) {
    console.log("请输入要删除的学生学号：");
    let number = readline.question() - 0;
    while (isNaN(number) || number < 1 || number > length) {
        console.log("输入有误:请重输");
        number = readline.question();
    }
    console.log("当前学生信息如下：");
    console.log(user1[number - 1]);
    console.log("确认删除请按1，返回请按2");
    let choice = readline.question() - 0;
    while (isNaN(choice) || choice < 1 || choice > 2) {
        console.log("输入有误，请重输：");
        choice = readline.question() - 0;
    }
    if (choice == 1) {
        user1.splice(number - 1, 1); //删除学号对应的对象
        length--; //数组长度减少1
        let a = ["id", "name", "age", "gender", "score"]; //用数组取对象键名
        let b = a[0]; //用变量b来表示对象的id属性
        for (let i = number - 1; i < user1.length; i++) {
            user1[i][b]--; //当删除一条对象之后，保证这条对象之后的对象的id属性-1
            console.log(user1[i]);
        }
        console.log("删除成功");
        return;
    } else {
        return;
    }
}
//选择操作
function operation(user1) {
    let status = true;
    while (status) {
        console.log("请选择操作：1.查询 2.新增 3.修改 4.删除 5.退出");
        let choice = readline.question() - 0;
        while (isNaN(choice) || choice < 1 || choice > 5) {
            console.log("请重输");
            choice = readline.question() - 0;
        }
        switch (choice) {
            case 5:
                console.log("谢谢使用，再见");
                status = false;
                break;
            case 4:
                del(user1, user1.length);
                break;
            case 3:
                alter(user1, user1.length);
                break;
            case 2:
                add(user1, user1.length);
                break;
            case 1:
                search(user1);
                break;
        }
    }

}

operation(user1);